Brisk Wind Advisory 50, NWS Fairbanks, AK

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
132 PM AKST THU FEB 5 2015

.DISCUSSION...

MODELS...GOOD AGREEMENT IN THE 12Z RUNS. INITIALIZED WELL AT 18Z
AT THE SURFACE. NO SIGNIFICANT DIVERGENCE IN THE MODELS UNTIL 132
HOURS OR SO. WILL USE A BLEND OF THE GFS AND ECMWF TO NUDGE THE
TEMPERATURES IN THE SHORT TERM.

ALOFT...AT 500 HPA...553 HPA BLOCKING RIDGE IS CENTERED JUST SOUTH
OF THE GULF OF ANADYR WITH ZONAL FLOW ACROSS THE WESTERN ARCTIC.
RIDGE REMAINS STATIONARY WITH THE ZONAL FLOW EXTENDING EAST TO THE
BEAUFORT SEA TODAY. NORTH TO NORTHEAST FLOW DEVELOPS OVER THE
MAINLAND AND WILL PERSIST THROUGH THE WEEKEND. A TROUGH OVER THE
SOUTHERN YUKON TERRITORY WILL DIG SOUTHWEST THIS EVENING WITH A
511 DAM LOW DEVELOPING OVER YAKUTAT AND BECOMING STATIONARY INTO
SATURDAY MORNING...THEN WEAKENS AND IS ABSORBED BY A 497 DAM LOW
THAT DEVELOPS OVER KODIAK ISLAND. A SHORTWAVE WILL DEVELOP NEAR
80N TONIGHT AND DIVE SOUTH TO THE ARCTIC COAST BEFORE NOON FRIDAY
WITH A 504 DAM LOW DEVELOPING FRIDAY AFTERNOON OVER PRUDHOE
BAY...THE LOW DISSIPATES RAPIDLY FRIDAY NIGHT AND IS ABSORBED BY
THE LOW OVER YAKUTAT...AND THE SHORTWAVE MOVES TO THE CANADIAN
ARCHIPELAGO BY SATURDAY MORNING. THE RIDGE WILL DRIFT BACK TO THE
WEST OVER SOUTHERN SIBERIA AS THE TROUGH DIGS IN OVER THE SOUTHERN
THIRD OF THE STATE. AT 850 HPA...20 BELOW CELSIUS ISOTHERM LIES
FROM BARROW TO YAKUTAT THIS MORNING WITH TEMPERATURES NEAR ZERO
CELSIUS OVER THE LOWER YUKON DELTA. THE 20 BELOW ISOTHERM WILL
MOVE WEST BY FRIDAY MORNING TO LIE FROM POINT HOPE TO BETTLES TO
DENALI AND BY FRIDAY NIGHT 20 BELOW OR COLDER TEMPERATURES WILL
LIE OVER ALL BUT THE LOWER YUKON DELTA. THE 20 BELOW ISOTHERM WILL
LIE FROM BARROW TO TOKSOOK BAY BY SATURDAY MORNING WITH 30 BELOW
OR COLDER TEMPERATURES OVER THE ARCTIC PLAIN AND FORTYMILE
COUNTRY. TEMPERATURES BEGIN MODERATING SUNDAY.

SURFACE...1038MB HIGH OVER THE NORTHERN YUKON TERRITORY EXTENDS
NORTHWEST TO A 1035MB HIGH OVER PRUDHOE BAY. THE HIGH WILL DRIFT
EAST WITH RIDGING EXTENDING INTO THE UPPER YUKON FLATS. A COLD
FRONT EXTENDS SOUTH TO THE BERING STRAIT AND WILL MOVE EAST ACROSS
THE ARCTIC COAST TONIGHT AND INTO CANADA BY FRIDAY AFTERNOON. A
SECOND FRONT NEAR 80 NORTH FRIDAY MORNING WILL MOVE SOUTH TO THE
ARCTIC COAST LATE FRIDAY...THEN SLOWLY DRAG EAST AND SOUTH
EVENTUALLY DISSIPATING OVER YUKON TERRITORY. RIDGING FROM A 1041MB
HIGH OVER NORTHERN SIBERIA WILL EXTEND EAST OVER THE CHUKCHI SEA
AND SOUTH OVER THE EASTERN BERING SEA BY EARLY FRIDAY AND PERSIST
INTO SUNDAY. A 1038MB HIGH WILL DEVELOP OVER THE ARCTIC PLAIN
SUNDAY MORNING. A 967MB LOW NEAR THE QUEEN CHARLOTTE ISLANDS WILL
MOVE NORTH TO PRINCE OF WALES ISLAND BY FRIDAY MORNING...THEN
MERGE WITH A 976MB LOW THAT DEVELOPS NEAR YAKUTAT FRIDAY
AFTERNOON. THE LOW WILL DRIFT TO SOUTH OF KODIAK ISLAND BY
SATURDAY EVENING...THEN MOVES BACK TO PRINCE WILLIAM SOUND SUNDAY
NIGHT AND DISSIPATES. A STRONG GRADIENT WILL DEVELOP OVER THE
NORTHEAST ARCTIC COAST FRIDAY MORNING AS THE SECOND FRONT DROPS
SOUTH AND PERSIST THROUGH SATURDAY MORNING. STRONG NORTH WINDS
WILL DEVELOP THROUGH THE ALASKA RANGE AS THE GRADIENT STRENGTHENS
FRIDAY NIGHT. NORTHEAST WINDS OVER THE HILLS WILL PICK UP AS THE
RIDGE REMAINS STATIONARY AND THE LOW MOVES INTO THE NORTHERN GULF
OF ALASKA.

ARCTIC COAST AND BROOKS RANGE...MOST ACTIVE AREA IN THE FORECAST
AREA. BIGGEST ISSUE WILL BE HAZARDS OVER THE NORTHEAST COAST AND
EASTERN BROOKS RANGE AS THE SECOND FRONT DROPS SOUTH FROM THE
HIGH ARCTIC AND WINDS INCREASE. NOT MUCH SNOW WITH THE FRONT SO
BLIZZARD POTENTIAL IS PRETTY LOW AND WINDS WILL ONLY BE MARGINAL.
WILL GO WITH WINTER WEATHER ADVISORIES FOR ZONES 203 AND 206.
KEEPING THE WIND CHILL FOR ZONE 203 BUT THAT MAY HAVE TO BE
MORPHED INTO SOMETHING ELSE LATER. CONDITIONS WILL IMPROVE
SATURDAY. WEAK WARM AIR ADVECTION TONIGHT...THEN COLD AIR
ADVECTION AS THE FRONT DIVES SOUTH.

WEST COAST AND WESTERN INTERIOR...GENERALLY QUIET CONDITIONS TO
CONTINUE THROUGH THE WEEKEND. COOLING TEMPERATURES AS THE
NORTHERLY FLOW KICKS. SOME PATCHY STRATUS NEAR THE BERING STRAIT
AND OVER THE CHUKCHI SEA WILL CONTINUE TO BRING LOW CEILINGS TO ST
LAWRENCE ISLAND AND MAY CREEP EAST OVER THE BERING STRAIT COAST.
EXPECT WINDS TO INCREASE AT HIGHER ELEVATIONS ACROSS THE AREA.

CENTRAL AND EASTERN INTERIOR...MOSTLY CLEAR AND COLDER THROUGH THE
WEEKEND. SOME WINDS OVER THE HILLS DEVELOPING FRIDAY AND
PERSISTING THROUGH THE WEEKEND. COLDEST AREAS WILL BE IN THE
FORTYMILE COUNTRY WITH TEMPERATURES FALLING INTO THE 50S BELOW.

4 TO 7 DAY EXTENDED...RIDGING WILL GIVE WAY AND BROAD AREA OF LOW
PRESSURE MOVES OVER THE AREA SOUTH OF THE BROOKS RANGE. WARMING
TREND WILL PUSH TEMPERATURES BACK UP TO SEASONAL NORMALS.

SATELLITE...SPORT MODIS 24 HOUR MICROPHYSICS AT 05/1308Z SHOWS
SOME STRATUS OVER THE NORTHWEST COAST...WITH SOME EXTENDING SOUTH
THROUGH THE WESTERN BERING STRAIT AND OVER ST LAWRENCE ISLAND AND
WEST OVER THE GULF OF ANADYR. DOES NOT LOOK LIKE MUCH MOVEMENT BUT
IT MAY DRIFT OVER THE BERING STRAIT COAST. LOOKS LIKE THERE MAY
ALSO BE SOME STRATUS OVER THE UPPER YUKON FLATS TO THE WEST OF
FORT YUKON. THE GOES MVFR/IFR PROBABILITY PRODUCTS ARE IN
AGREEMENT THAT THERE IS SOMETHING IN THOSE AREAS.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...

WIND CHILL ADVISORY FOR AKZ203-AKZ207.

WINTER WEATHER ADVISORY FOR AKZ204-AKZ206-AKZ218.

BRISK WIND ADVISORY FOR PKZ210-PKZ230-PKZ235-PKZ240-PKZ245.

&&

SDB FEB 15